1. Field of the Invention
The present invention relates to a videophone video and audio transfer system, a mobile communication terminal, and a videophone video and audio transfer method used for the same, and more particularly to a videophone video and audio transfer method used in mobile communication terminals.
2. Description of the Related Art
In recent years, with a mobile communication terminal equipped with an imaging device, such as a CCD (Charge Coupled Device) and a CMOS (Complementary Metal Oxide Semiconductor), still images or moving images can be captured, and a videophone call can be made (refer to Japanese Patent Laid-Open No. 2000-032421, for example).
In a mobile communication terminal according to conventional art, images captured with the above described imaging device and sounds picked up with a microphone are transmitted as videophone video and audio to a call destination, and at the same time, videophone video and audio received from the call destination can be outputted only through a built-in LCD (Liquid Crystal Display) and built-in loudspeaker.
In the mobile communication terminal according to conventional art, however, much power is consumed to display images on the built-in LCD. Consequently, a call state cannot be maintained for a long time, thereby causing a problem.
Also, in the mobile communication terminal according to conventional art, its built-in LCD is small. Thus, it is impossible for many persons to view the videophone images.
In the mobile communication terminal according to conventional art, when the videophone function is used, more current is consumed by using the videophone video display unit as compared with when only the call function is used. Thus, the use of videophone function leads to a significantly reduced communicatable time.
Also, in the mobile communication terminal according to conventional art, it is supposed that videophone is used for videoconference, etc. However, with the display unit mounted on the mobile communication terminal, the image size of persons, etc. is too small to be used for a case in which a large range must be displayed, such as a conference held by many people, thus limiting the application of the videophone.
The solutions to this problem include a wired power supply and a wired video and audio transfer. However, these methods can reduce the freedom of movement, which is one feature of a mobile communication terminal.